James p



(-No Model.)

J. P. FREEMAN.

LIGHTNING ARRESTER GUT-OUT.

Patented Aug. 30, 1892.

II I I Lana UNITED STATES PATENT OFFICE.

JAMES P. FREEMAN, OF WVASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR OF TW'O-TI-IIRDS TO MARVIN C. STONE AND PHILIP T. DODGE, OF SAME PLACE.

LlGHTNlNG-ARRESTER CUT-OUT.

SPECIFICATION forming part of Letters Patent No. 481,617, dated August 30, 1892.

Application filed December 24,1891. Serial No. 416,018. (No model.)

To all whom it may concern.-

Be it known that I, JAMES P. FREEMAN, of Washington, in the District of Oolu mbia, have invented a new and useful Improvement in Lightning-Arresters, of which the following is a specifiation.

The aim of my invention is to provide a simple and durable device for protecting telephones and other instruments in electric cir- Io cuits from injury by lightning or other abnormal currents by cutting out the instrument and grounding the line during the continuance of the danger and then automatically restoring the original connections and this without employing fusible conductors or placing an increased resistance in the line. To this end I control the line by a magnetic needle, making use of the fact that the needle has a tendency to stand transverse to the course of the current to cause its change of position when the abnormal current is received.

My invention may be embodied in various equivalent forms; but I have represented in the drawings an instrument which is recommended on account of its extreme simplicity and reliability.

Referring to the accompanying drawings, Figure 1 is a perspective view of the same, and Fig. 2 a cross-section on the line 2 2.

In the drawings, A represents a non-conducting base-plate, B an arched metal conducting bar or strip secured thereto and connected at one end with the line-wire (l, and D is a magnetic needle sustained at the mid- 5 dle by and insulated from a vertical spindle E, seated at the upper end in an insulated bearing F in screw G and at its lower end in contact with an underlying arm 17 of the arched bar B.

H is a fixed insulated conducting-plate connected with the line-wire M and normally in contact with a conducting-pin d, carried by the needle, the pin being preferably connected with the axis of the needle by a con- 5 ducting-strip I, attached to the needle. This strip and the spindle or axis may both be insulated from the needle, as shown, and this is the preferred construction; but the strip may be omitted and the circuit completed directly through the needle.

K is a second insulated conductor fixed to the base and connected with the ground-wire L and normally out of contact with the pin (1 of the needle. Under normal conditions the circuit is completed through line-wire 0, bar B, its arm I), spindle E, strip I, pin d, and plate II to line M.

N is a permanent magnet secured to the base near one end of the needle transversely, so that it aids by its attractive influence in keeping the needle in its normal position and maintaining the circuit.

It will be observed that the current flows through the device in the direction of the length of the needle, so that it tends to cause the latter to swing around to a transverse position. The parts are so adapted, however, as to maintain their places under ordinary conditions. If, however, an abnormally-magnetic current enters the line it will overcome the polar tendency of the needle and the influence of the magnet and cause the needle to swing until the pin leaves the plate H and opens the main line and contacts with plate K, thereby establishing a ground connection, which continues until the weakening of the current permits the needle to return to its original position, thus opening the ground and restoring the line.

Having thus described my invention, what I claim is 1. In a lightning-arrester, the combination of a magnetic needle, means for directing the current lengthwise of the needle, and main-line and ground connections opened and closed alternately by the vibration of the needle.

2. The base, the arched conductor, and the needle, in combination with the line and the ground contacts at opposite sides of the needle.

3. In combination with the needle, the line and the ground contacts, through which the current is directed by the needle, the auxiliary magnet, and means for directing the current lengthwise of the needle, substantially as described.

In testimony whereof I hereunto set my hand this 16th day of December, 1891, in the presence of two attesting witnesses.

JAMES P. FREEMAN.

Witnesses:

W. R. KENNEDY, W. H. SHIPLEY. 

